Saturday, September 13, 2008

You've been in the pipeline

Most water users in the U.S. pay a price for water that reflects the cost of delivery. The price of water is actually zero. Although the fixed costs of dams, pipes, etc. and the variable costs of pumping (20 percent of California’s energy is used for “moving water”) are large in aggregate, those costs are spread across many units of water. In southern California, for example, urban water customers pay about $3 for 750 gallons of tap water, most of which is imported from hundreds of miles away.
-- David Zetland

If we can transport 750 gallons of water (over 6000 pounds) for hundreds of miles for $3, why can't we transport other things (e.g. people) equally cheaply?


At 3:10 PM, September 16, 2008, Blogger badmomgoodmom said...

For the most part, water is transported downhill. When it goes over a pass, water is pumped uphill using power generated by the water falling down the other side (+ some extra energy from another source).

That's why it is the Department of Water and Power. DWP generates enough electricity from moving water that they became a major player in energy generation.

Can you do that with humans?

At 8:56 AM, September 17, 2008, Blogger Richard Mason said...

It is a good point about going downhill, but... both Lake Mead and Lake Powell are at 3700 feet or 1125 meters. The gravitational energy available from 750 gallons of water (2839 kg) descending to sea level is 31 megajoules or 8.7 kilowatt-hours.

At California rates an electric kilowatt-hour is about fifteen cents, so call it $1.35 worth of energy.

Now the dams we actually get most of our water from are at much lower elevations! Parker Dam is at 450 feet which is just one kilowatt-hour or 15 cents of energy. Oroville Dam is at 900 feet... two kilowatt-hours.

If you can pump water from Parker Dam to Los Angeles for $3, you should be able to pump water from Los Angeles to Parker Dam for about $3.15.

At 8:58 AM, September 17, 2008, Blogger Richard Mason said...

As to whether you can use humans going downhill to lift humans going uphill... yes you can!

I guess the Falkirk Wheel that Maribeth and I have ridden on is exactly the execution of that concept.


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